The Economics of Regional Poverty-Environment Programs: An Application for Lao People's Democratic Republic

Program administrators are often faced with the difficult problem of allocating scarce resources among regions in a country when interventions are aimed at addressing multiple objectives. One main concern is the tradeoff between poverty reduction and improvement of environmental quality. To provide a framework for analysis, the authors develop a model of optimal budget allocation that allows for variations in three factors: administrators'valuation of objectives; their willingness to accept tradeoffs among objectives and regional allotments; and regional administrative costs. The results from an application of this model using information for Lao People's Democratic Republic show that simple poverty indicators alone do not provide consistent guidelines for policy. However, when different poverty indicators are embedded in an optimizing model that incorporates preferences and costs, the resulting provincial allocations are very similar. This suggests that adoption of a formal analytical approach to resource allocation can help promote the harmonization of regional policy guidelines.Poverty Reduction Strategies,Public Health Promotion,Health Economics&Finance,Environmental Economics&Policies,Poverty Monitoring&Analysis,Environmental Economics&Policies,Poverty Assessment,Poverty Reduction Strategies,Poverty Monitoring&Analysis,Health Economics&Finance

On solving the assembly line worker assignment and balancing problem via beam search

Certain types of manufacturing processes can be modelled by assembly line balancing problems. In this work we deal with a specific assembly line balancing problem that is known as the assembly line worker assignment and balancing problem (ALWABP). This problem appears in settings where tasks must be assigned to workers, and workers to work stations. Task processing times are worker specific, and workers might even be incompatible with certain tasks. The ALWABP was introduced to model assembly lines typical for sheltered work centers for the Disabled. In this paper we introduce an algorithm based on beam search for solving the ALWABP with the objective of minimizing the cycle time when given a fixed number of work stations, respectively, workers. This problem version is denoted as ALWABP-2. The experimental results show that our algorithm is currently a state-of-the-art method for the ALWABP-2. In comparison to results from the literature, our algorithm obtains better or equal results in all cases. Moreover, the algorithm is very robust for what concerns the application to problem instances of different characteristicsBlum, C.; Miralles Insa, CJ. (2011). On solving the assembly line worker assignment and balancing problem via beam search. Computers and Operations Research. 38(1):328-339. doi:10.1016/j.cor.2010.05.008S32833938

Productivity effects of public capital maintenance: Evidence from U.S. states

This article assesses the productivity effects of infrastructure operation and maintenance (O&M) spending by state and local governments in the 48 contiguous U.S. states over the period 1978-2000. We explicitly account for transboundary spillovers of capital and O&M spending and follow a semiparametric methodology that allows us to estimate state-specific output elasticities. We find strong evidence that in all 48 states the cross-state spillover effects of O&M outlays on productivity exceed their within-state impacts and are substantially higher than the spillover effects of capital expenditure. (JEL C14, E22, E62, H76, O11, O47, R11)

Pleosporales

One hundred and five generic types of Pleosporales are described and illustrated. A brief introduction and detailed history with short notes on morphology, molecular phylogeny as well as a general conclusion of each genus are provided. For those genera where the type or a representative specimen is unavailable, a brief note is given. Altogether 174 genera of Pleosporales are treated. Phaeotrichaceae as well as Kriegeriella, Zeuctomorpha and Muroia are excluded from Pleosporales. Based on the multigene phylogenetic analysis, the suborder Massarineae is emended to accommodate five families, viz. Lentitheciaceae, Massarinaceae, Montagnulaceae, Morosphaeriaceae and Trematosphaeriaceae

A branch and cut approach for certain problems in assembly systems

Vita.This research addresses certain problems associated with assembly systems, namely the assembly line balancing problem (ALBP), the workload smoothing problem (WSP), and the single-product assembly system design problem (ASDP). The ALBP prescribes task assignments which minimize the number of stations; the WSP, task assignments which minimize the maximum idle time at all stations in a line of a specified number of stations; and the ASDP, machine types and task assignments such that total cost is minimized. Motivated by the success of strong cutting plane methods in solving a variety of problems and the fact that inequalities that are valid for a polytope are also valid for more complex problems in which the polytope is embedded, this research begins by studying the polyhedral structure of the ALBP. The node packing problem defined on the intersection graph which is constructed by certain rules is shown to represent a relaxation of the ALBP. Consequently, several families of valid inequalities are derived and proven that under certain conditions they define facets for the associated polytopes. A polynomial separation algorithm is devised for each family of valid inequalities. In addition, preprocessing methods are described to decompose and reduce a precedence graph as well as to estimate bounds on parameters that are involved in valid inequalities. A branch and cut algorithm is implemented for the WSP, directly incorporating the separation algorithms and preprocessing methods for the ALBP, which is embedded in the WSP. Similarly, valid inequalities for the ASDP are derived by extending the inequalities that have been shown to be valid for the ALBP. Consequently, a branch and cut method is implemented for solving the ASDP, adapting the separation algorithms and preprocessing methods that have been devised for the ALBP. Computational results that evaluate the efficacy of the branch and cut approaches for both the WSP and the ASDP clearly demonstrate that the branch and cut algorithms can achieve an order of magnitude improvement in runtimes and the number of nodes enumerated. In fact, the branch and cut techniques are shown to be powerful and offer promise for other problems as well

Public infrastructure and private economic performance : evidence from U.S. panel data

Vita.Government can affect private economic activities through many means: the legal system and regulatory mechanisms, the tax and subsidy systems, lending and other monetary activities, and the services from public infrastructure. This dissertation investigates the potential contribution of public infrastructure to private economic activities. Importantly, this research attempts to provide an answer to the question: is public infrastructure undersupplied? The contribution of different types of public infrastructure (i.e.. highways and streets, water and sewer systems, and other public buildings) on private production is investigated using time-series and cross-sectional data of the 48 contiguous states over the period of 1970-1986. A Cobb-Douglas production function is estimated with unobserved state-specific effects. Measurement errors in the total public capital stock and its components are detected and rectified. It is found that water and sewer facilities (and in most cases, highways and streets) consistently provide productive contributions to private productivity. This study also attempts to identify the contribution of different types of public infrastructure to regions and industries. The error component model is specified using the translog production function. The results show that regions and industries do not react uniformly to various types of public investment. For example, transportation infrastructure is more productive with respect to the agricultural sector in the Northeast than in any other regions and industries. To answer the undersupply question, the short-run variable cost function is utilized. The system of first-order conditions is estimated by Iterative Seemingly Unrelated Regressions. The main result shows that both private and public capital have been under-capitalized in the sense that their long-run desired levels are greater than their actual levels. Finally, the internal rate of return to quasi-fixed inputs are provided. In conclusion, the relationship between public infrastructure and private economic performance is a complex one. Nevertheless, the positive contribution of public capital is discovered. Both private and public capital have not reached their long-run equilibrium levels. However, this does not imply that the level of total tangible capital should be raised without a careful cost-benefit analysis

A branch and cut approach for certain problems in assembly systems

Vita.This research addresses certain problems associated with assembly systems, namely the assembly line balancing problem (ALBP), the workload smoothing problem (WSP), and the single-product assembly system design problem (ASDP). The ALBP prescribes task assignments which minimize the number of stations; the WSP, task assignments which minimize the maximum idle time at all stations in a line of a specified number of stations; and the ASDP, machine types and task assignments such that total cost is minimized. Motivated by the success of strong cutting plane methods in solving a variety of problems and the fact that inequalities that are valid for a polytope are also valid for more complex problems in which the polytope is embedded, this research begins by studying the polyhedral structure of the ALBP. The node packing problem defined on the intersection graph which is constructed by certain rules is shown to represent a relaxation of the ALBP. Consequently, several families of valid inequalities are derived and proven that under certain conditions they define facets for the associated polytopes. A polynomial separation algorithm is devised for each family of valid inequalities. In addition, preprocessing methods are described to decompose and reduce a precedence graph as well as to estimate bounds on parameters that are involved in valid inequalities. A branch and cut algorithm is implemented for the WSP, directly incorporating the separation algorithms and preprocessing methods for the ALBP, which is embedded in the WSP. Similarly, valid inequalities for the ASDP are derived by extending the inequalities that have been shown to be valid for the ALBP. Consequently, a branch and cut method is implemented for solving the ASDP, adapting the separation algorithms and preprocessing methods that have been devised for the ALBP. Computational results that evaluate the efficacy of the branch and cut approaches for both the WSP and the ASDP clearly demonstrate that the branch and cut algorithms can achieve an order of magnitude improvement in runtimes and the number of nodes enumerated. In fact, the branch and cut techniques are shown to be powerful and offer promise for other problems as well

Public infrastructure and private economic performance : evidence from U.S. panel data

Vita.Government can affect private economic activities through many means: the legal system and regulatory mechanisms, the tax and subsidy systems, lending and other monetary activities, and the services from public infrastructure. This dissertation investigates the potential contribution of public infrastructure to private economic activities. Importantly, this research attempts to provide an answer to the question: is public infrastructure undersupplied? The contribution of different types of public infrastructure (i.e.. highways and streets, water and sewer systems, and other public buildings) on private production is investigated using time-series and cross-sectional data of the 48 contiguous states over the period of 1970-1986. A Cobb-Douglas production function is estimated with unobserved state-specific effects. Measurement errors in the total public capital stock and its components are detected and rectified. It is found that water and sewer facilities (and in most cases, highways and streets) consistently provide productive contributions to private productivity. This study also attempts to identify the contribution of different types of public infrastructure to regions and industries. The error component model is specified using the translog production function. The results show that regions and industries do not react uniformly to various types of public investment. For example, transportation infrastructure is more productive with respect to the agricultural sector in the Northeast than in any other regions and industries. To answer the undersupply question, the short-run variable cost function is utilized. The system of first-order conditions is estimated by Iterative Seemingly Unrelated Regressions. The main result shows that both private and public capital have been under-capitalized in the sense that their long-run desired levels are greater than their actual levels. Finally, the internal rate of return to quasi-fixed inputs are provided. In conclusion, the relationship between public infrastructure and private economic performance is a complex one. Nevertheless, the positive contribution of public capital is discovered. Both private and public capital have not reached their long-run equilibrium levels. However, this does not imply that the level of total tangible capital should be raised without a careful cost-benefit analysis